Abstract: The present invention improves accuracy in the axial dimension of rolled parts for a chain such as bushings, rollers and similar. A rolled part is manufactured by cutting a strip of steel into a rectangular shape to obtain a rectangular base material having a predetermined dimension, The rectangular base material is rolled into a clindrical shape to obtain a cylindrically formed part having cut end surfaces face each other. A core is inserted for rolling the rectangular base material into the cylindrically formed part. The cylindrically formed part is then pressed through a die having a circular opening. The rolled part has a plurality of blind grooves on a surface thereof. While the cylindrically formed part is being pressed through the die having a circular opening, a plastic flow of the material of the cylindrically formed part intensively occurs in a direction toward the blind grooves.

Abstract: A link assembly for a chain comprising a link portion, a top plate portion having a top surface and a bottom surface made of a predetermined first material, and a plate member made of a different material than the top plate portion and integrally molded to at least the one of the top or bottom surfaces of the top plate portion.

Abstract: An improved rocker joint pin type CVT chain has link plates connected by rocker joints, each including a rocker pin and a seat pin in an insertion bore of the link plate, the rocker pin and the seat pin making rolling contact along opposing rolling arcuate surfaces thereof as the chain bends and straightens when passing around a pulley. At respective minimums, the sectional area of the link plate formed between the link plate insertion bore and the outer periphery of the link plate relative to the pulley, is greater than the sectional area formed between the link plate insertion bore and the inner periphery. The radii of curvature of the inner rolling contact surfaces of the rocker pin and seat pin are smaller than those of the outer rolling contact surfaces.

Abstract: An improved friction drive chain especially for a continuously variable transmission has a plurality of friction plates, each of the friction plates being substantially I-shaped in lateral section. The friction plates are arranged adjacent one another and connected by connecting link elements received in recesses formed in both lateral sides of the friction plates between upper and lower beam members of said friction plates. The connecting link elements are laterally grooved to bear longitudinally against the friction plates. The outer surfaces of the lower beam members of the plates define friction drive surfaces for contact with driving and/or driven pulleys. The friction plates are heat treated to increase strength, for example by quenching and annealing. The friction drive surfaces are formed with hardened layers by surface hardening treatment such as by electron beam or laser.